Influence of the spatial layout of plant roots on slope stability

Abstract

Background and aimsTechnology involving the use of plants on slopes to prevent shallow landslides and slope instability has been extensively used worldwide. A reasonable collocation of plant and engineering measures can prevent water loss and soil erosion effectively. Because of the complicated distribution of roots in soil, there must be a simpler and more workable method of studying the role of plant roots on slope stability. The purpose of this paper is to investigate the affects of shallow-rooted plants on slope stability and provide reliable theoretical support in the process of ecological environmental constructions. MethodsHere we used numerical simulations to examine the influence of plant roots on soil shear strength as the increase of soil cohesion. Then, we generalized root architecture to be soil bodies consisting of different cohesive strengths. Changes of stress and pressure were simulated within the range of soil within plant roots on the slope. The intensity attenuation method was here used to calculate the safety factor of slope. ResultsTapered roots were found to be associated with more serious soil loss due to the maximal velocity of 14m/s within the scope of plant main stems. Widely root distribution in H-type showed a cyclical effect on the slope on condition that flow shear stress was small. ConclusionsYoung trees have little impact on slope stability which is 3.76–7.85% merely comparing to the bare slopes regardless of rainfall. When root distributions are similar in topsoil, the resistances to the radial stress are not obvious. Widely distributed (H-type) and tapered root (VH-type) architecture are recommended in biological engineering projects.